Buffing fixture for dry shaver cutterheads



Apw 25 H95@ T. J. MURPHY- BUFFING FIXTURE FOR DRY sHAvER CUTTERHEADS Filed May 8 1946 ATTORNEYSl ...ma sun Patented Apr. 5, 195@ nur BUFFENG FIXTURE FOR DRY SHAVER CUTTERHEADS Thomas J. Murphy, Stamford, Conn.

Application May 8, 1946, Serial No. 668,164

'7 Claims.

This invention relates to a bufng xture for the cutter head of dry Shavers, more particularly to a holder for holding the outer cutters of a dry shaver cutter head during the leuning operation in finishing these cutters, and has for an object to provide a simple and effective holder for holding the cutter elements in proper relation to each other and also to support the cutting teeth during the buiTing operation so as to secure uniform and accurate buiing of all of the teeth of the cutter, and prevent hurling oi too much of the tips of the teeth, so they will not be made too sharp with the liability of causing irritation when shaving.

Another object is to reduce to a minimum variations in buing due to variations `in pressure of the article against the buiiing wheel` A further object is to increase control of the operator over the buning operation.

With the foregoing and other objects in view, I have devised the construction illustrated in the accompanying drawing forming a part of this speciiication. It is, however, to be understood the invention is not limited to the specific details of construction and arrangement shown, but may embody various changes and modifications within the scope of the invention.

In this drawing:

Fig. 1 is a side elevation of one form of my improved xture with a plate of the cutter head clamped in position for buing;

Fig. 2 is an end view thereof;

Fig. 3 is a top plan view of one end portion thereof;

Fig. 4 is an end view showing a slight modification;

Fig. 5 is a transverse section of one form of cutter head;

Fig. 6 is a top plan view of a portion thereof;

Fig. '7 is a vertical section of one of the cutter plates removed;

8 is a top plan view thereof;

Fig. 9 is an elevation looking from the right of Fig. 7;

Fig. l0 is an end view of the upper portion of the xture with cutter plates clamped thereon showing how the device may be modied for different cutters; and

Figs. 11 and 12 are similar views showing other ways the holder may be modified for different builing effects.

This device is designed primarily for use in buiiing cutter heads of the type comprising separate side plates each carrying a row of the outer cutter teeth oi the cutter head of an electric dry shaver of the type disclosed in my Patents No.

2 2,264,398, December 2, 1941, and No. 2,395,495, February 26, 1946. Such a cutter head is illustrated somewhat diagrammatically in Figs. 5 and 6, the individual plate of the outer cutter being shown separated from it in Figs. '7, 8 and 9.

It is to be understood that in all views of the drawing the scale is greatly enlarged and features are also exaggerated, because the actual cutter heads themselves are quite small and dimensions are figured in thousandths of an inch.

The type of cutter head shown in Figs. 5 and 6 comprises a central block I Ii on the opposite sides of which are secured plates II by any suitable means, as by clamping means cr soldering, which plates are wider than the block so as to extend a suitable distance above it, and each at its separate edge terminates in an inturned iiange I2 provided o`n its free edge with a series of cutter teeth I3. The iiange and the teeth are at an angle of about 1`0`0 degrees with the plate i I so that they incline upwardly toward the center, as shown in Fig. 5,` so that they are adapted for a certain amount of lateral rocking back and forth when pressed against the surface of the skin in the shaving operation to maintain them in proper contact with the skin, and also to facilitate movement over the Surface of the skin, all as clearly disclosed in the above noted patents. The block i0 is of such a width in relation to the Width of the nanges I2 that when the plates areV mounted on the block the free ends of the teeth I3 of the outer cutter are spaced laterally to form allongitudinal slot I4. In the space between these plates, their flanges and the top of the block I0 is the reciprocating cutter It which is substantially rectangular in cross section and hollow and is guided for reciprocating movement on the block I0 andbetween the side plates I I. On its top it is provided with two sets of cutter teeth IB, running on the inner side of the outer teeth I3 and cooperating therewith to cut the hairs during the shaving operation with a shearing action in the well known manner. The movable cutter |15 is op- @rated by any suitable motor (not shown) through any suitable driving connection, indicated as an operating, rod il. It will be understood this head is mounted in one end of the casing` enclosing the motor andwhich forms a handle for pressing the cutter head against thesurface of the skin and moving it thereover during the shaving operation; but these elements are not shown as they form no part of this invention.

In` making the device the plates i I4 forming the outer cutter ofthel head are made and finished separately and then assembled. The nnal operation in finishing the cutter teeth I3 is the buffing operation, and in bufflng such single elements the operator is liable to remove too much metal from the tips of the teeth, it being understood that the teeth are Very small and thin in order to bring the cutting or shearing plane as close as possible to the surface of the skin to secure a close shave. Removing too much metal from the tips of the teeth is liable to make them too sharp, with the result that they cause irritation while shaving. Also, the buing may substantially shorten the teeth, which would be serious in some types of cutters, especially the types of cutters using very short teeth. Also when buried unsupported, as the outer surfaces of the teeth are pressed against the bung wheel they will yield so that the operator does not have good control and the pressure may Vary from one plate to another, thus not giving uniform bumng for different plates.

I have found that if the plates of the cutters are clamped on the fixture and opposed to one another so that the teeth on the two elements register, and the teeth are backed up or supported on the opposite side from the surface held against the buliing wheel, there is no danger of removing too much metal from the tips of the teeth, and the buing can be continued longer with a coarser abrasive so that the upper surrounding edges of the teeth will be rounded 01T, and when assembled in the head will bring the inner movable cutter closer to the surface of the skin and will therefore produce a closer and smoother shave with less irritation to the skin. Such a device for holding the cutter plates is shown in Figs. 1 to 4 and 10 to 12, and While there are many other ways of clamping and holding the plates on the fixture, that shown is very simple and effective and may be quickly operated to secure and release the plates.

This xture comprises a body or block I8 preferably of metal inclined in its upper portion on its opposite sides I9 to which the plates II of the cutter head are clamped, corresponding to the angle between the body of the plate and its flange I2 on which the cutting teeth are formed,

so that the teeth will rest against the upper edge 2U. As indicated above, this angle is preferably about 100 degrees and is indicated at 2l on the drawing, but it is to be understood that neither the block nor the cutter head plates are limited u to this specific angle, as it may be found desirable under diiferent conditions to Vary it somewhat either way. As indicated, the cutter head plates II are clamped on the opposite side walls I9 of this block with the teeth I3 resting against *l the top edge of the block, as shown in Fig. 2.

Any suitable means may be used for clamping these plates, but that shown comprises the knurled nuts 22 each threaded on a screw 22a secured in the block. One way is by threading l ,1

sults should be in alignment when assembled on the block, as shown in Fig. 3, and to assure proper alignment of the teeth one or more slots 23 can be punched and ground to accurate width to engage over one or more locating pins 24 mounted in the block. The block may be of such a Width that the tips of the opposed teeth touch each other, or they could be somewhat spaced, as is found desirable. It may in some cases be best that a small space be left between them, so that the buffng wheel may enter for the bufng operation.

It will be understood that as the outer surfaces of these teeth are held against the bufng wheel, a portion of which is indicated in dotted lines at 25, Fig, 2, the teeth are supported by the block I8, so that they do not yield and the pressure can be more accurately controlled and a much better and more uniform job can be done. Besides, two plates can be buifed at the same time, thus increasing production as well as producing a better cutter. Each plate automatically protects the other so that the teeth are protected and there is not too much of their tips buffed off to make them too sharp with the liability of causing irritation in shaving. If desired, hand grips 26 may be provided on opposite ends o1" the block I8. It is preferred that the length of the upper portion of the block I8 be made less than that of the cutter plates II, so that they will overhang somewhat as shown at 9 in Figs. 1 and 3 to protect the xture from the bufing compound.

In the modied arrangement of Fig. 4, the block 2 corresponding to the block I3 is relieved or provided with a longitudinal central channel 28 in its upper edge and the cutter plates Il are mounted the same as in Figs. l to 3, but the teeth i3 may be spaced a short distance because of this channel, but should practically contact each other. They will be supported on the end portion Z9 of the block, the same as in the first arrangement. The channel 28 is to collect bufng material, or, that is, to prevent caking of grinding compound between the teeth in the bufng operation.

If wider slots are used between narrower teeth, the buing is more effective in rounding o upper edges of the teeth in the outer shaving member. While the teeth in Figs. 2 and 4 are shown in substantially the same plane, they may be slightly depressed in the center, as shown at 3S in Fig. 11, or they can be slightly raised as shown at 3l in Fig. 12, these arrangements being exaggerated in the drawing. Also the clamping plates 35 are omitted in these figures, but it is to be understood such clamping plates are used to hold the cutter plates II the same as shown in Figs. l and 2. Whether they are in the same plane, depressed in the center or slightly raised, may be controlled by the angle of inclination of the side walls of the block. Thus, in Fig. 2 the end wall 29 is made substantially horizontal and the clamping side Walls I9 are at an angle substantially equal to the angle between the body of the plate II and the ange I2. In the arrangement of Fig. l1 the end wall may be left horizontal or slightly depressed in the center, and the side walls, indicated at ISa, of the block Ia, inclined ata greater angle, the angle corresponding to the.

angle 2 I being shown in dotted lines 32. In Fig. 12, the sides ISb of the block I 8b are inclined at a less angle, the old angle being shown by the dotted lines 33. Then when the plates II are clamped to these walls, the teeth will be raised slightly in the center, as indicated at 3|. and therefore the end walls 3d may be similarly inclined or raised somewhat at the center so as to provide support for the teeth I3 during the bufling operation. In the use of very short teeth, the side walls corresponding to the walls I9 may be made straight or parallel, as indicated at ISC in Fig. 10.

In this case the angle between the body of thek plate lla and the flange |211 is substantially a right angle, the upper `portion of the block being shown at |8c.

These figures show how the block may be varied to accommodate different cutter plates and also for diierent types of builng operations, and still have the teeth supported by the block during bufng.

In production, the teeth on the plate can be punched and consequently the tips and base slots between the teeth can be rounded or any approximation thereof for best results. All burs left by the punch on the inner or under sides of the teeth are removed by grinding and lapping.

Having thus set forth the nature of my invention, I claim:

l. A buiiing fixture for cutter head plates which plates each include a body and a riange at one edge extending laterally to the body and provided with a series of teeth on free edge, said xture comprising a block provided with opposite side walls and an intermediate wall arranged with the side walls each at an angle to the intermediate wall equal to substantially the angle between the body and flange of the plates, and means for clamping the bodies of .a pair of said plates against the opposite side walls of the block with the teeth of each plate resting against the intermediate wall and supported thereby.

2. A buiflng fixture for cutter head plates which plates comprise a body plate portion and a lateral ange at one edge terminating in a row of cutter teeth, said xture comprising a block provided with opposite side walls and an intermediate wall connecting them, and means for clamping a pair of said cutter head plates against the opposite side walls of the block, said clamping means being arranged to clamp the body plate portions against the side walls of the block with the teeth of said plates resting on and supported by the connecting intermediate wall.

3. A bufling nxture for cutter head plates which plates comprise a body plate portion and a lateral ilange at one edge terminating in a row of cutter teeth, said iixture comprising a block provided with opposite side walls and an intermediate wall connecting them, the side walls being inclined toward each other outwardly toward said intermediate wall, and means for clamping said cutter head plates to the block with their body plate l portions against the side walls of the block and the teeth resting on the intermediate wall.

4. A bufling fixture for holding cutter head plates which head plates comprise a plate like body portion and a lateral ange along one edge terminating in a row of cutter teeth, said fixture comprising a block including opposite side walls and an intermediate wall between them arranged at an angle to each side wall substantially the same as the angle between the body and the ange of said head plate, and means for clamping the plates on the block with their body portion against said side walls of the block and with their teeth on the intermediate wall and supported thereby.

5. A buiing fixture for holding cutter head plates which head p1ates comprise a plate like body portion and a lateral flange extending at an angle to the plate like portion along one edge terminating in a row of cutter teeth, said fixture comprising a block including spaced side walls and an intermediate wall connecting the side walls, each said side and intermediate walls being at an angle to each other substantially the same as the angle between the body and ilange of the head plates, means for clamping a pair of said p1ates on the opposite sides of the block arranged with one body portion on each side wall of the block and with its teeth on the intermediate wall and with the tips of the two rows of teeth adjacent, and locating means on the block arranged to cooperate with means on the plate to locate the teeth of the two plates in alignment.

6. A buiiing xture for holding cutter head plates which head p1ates comprise a plate like body portion and a lateral ange along one edge terminating in a row of cutter teeth, said fixture comprising a block including opposite side walls and an intermediate wall between them arranged at an angle to each side wall substantially the same as the angle between the body,r and the flange of said head plate, hand grips extending outwardly from the opposite ends 0f the block, and means for clamping the plates `against the opposite sides of the block. with their body portions against said side walls of the block and with their teeth on the intermediate wall and supported thereby.

7. A buffing xture for holding cutter head plates which head p1ates comprise a plate like body portion and a lateral flange along one edge terminating in a row of cutter teeth, said fixture comprising a block including spaced side walls and an intermediate wall located between the side walls, each said side and intermediate wals being at an angle to each other substantially the same as the angle between the body and flange of the head plates, means for clamping a pair oi said plates on opposite sides of the block arranged with one body portion on each side wall of the block with teeth of the p1ates on the intermediate wall and supported thereby, said intermediate wall being of a width so that the tips of the teeth of the two plates practically contact, and said block being provided with a longitudinal groove in said intermediate wall under the tips of the teeth of the two plates.

THOMAS J. MURPHY.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 643,914 Shaw Feb. 20, 1900 1,252,612 Perry Jan. 8, 1918 1,583,013 Sawtelle May 4, 1926 2,240,264 Muros Apr. 29, 1941 2,298,962 Murphy Oct. i3, 1942 2,362,306 Ringzelli Nov. 7, 1944 2,362,501 Salabes Nov. 14, 1944 FOREIGN PATENTS Number Country Date 13,730 Switzerland Feb. 18, 1897 

